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An increment in energy efficiency by employing nanoparticles is a hot topic of research in present era due to its abundant implications in modern engineering and technological processes. Therefore, the current research analysis reported the viscoelastic nanofluid flow over porous oscillatory moving sheet in the presence of microorganisms. A rate-type fluid namely Maxwell fluid is employed with the addition of nanoparticles. The paper aims to discuss this issue.

First, acceptable dimensionless variables are defined to convert the system of dimensional form into the system of dimensionless forms. Later on, the self-similar solution of the boundary value problem is computed by using the homotopy analysis method. The obtained results of velocity, temperature, mass concentration and motile microorganism density profiles are interpreted through physical background.

The presence of both thermophoresis and Brownian motion parameters also improve the thermophysical features of non-Newtonian nanoparticles. It is also pointed out that the presence of porous medium and magnetic force enhances the nanoparticles concentration. Moreover, a weaker distribution of gyrotactic microorganism has been depicted with Peclet number and bioconvection Lewis parameter.

No such article exists in the literature yet.

The purpose of this paper is to introduce the concept of improved Fourier–Fick laws subjected to variable fluid characteristics. Flow analysis in the stagnation region of Oldroyd-B fluid is elaborated. Heat generation is present.

Optimal homotopy analysis method is used to obtain convergent solutions.

The outcomes reveal reduction in penetration depths of temperature and concentration due to involvement of thermal and solutal relaxation times of fluxes.

As per the authors’ knowledge, such analysis has not yet been reported.

The nonlinear density thermal/solutal fluctuations in the buoyancy force term cannot be ignored when the temperature/concentration difference between the surface and fluid is large. The purpose of this paper is to investigate the nonlinear density fluctuations across a flowing fluid with heat mass transfer effects on a non-axial rotating plate. Therefore, the impact of nonlinear convection in the flow of Casson fluid over an oscillating plate has been analytically investigated.

The governing equations are modeled with the help of conservation equations of velocity, energy and concentration under the transient-state situation. The dimensional governing equations are non-dimensionalized by utilizing non-dimensional variables. Later, the subsequent non-dimensional problem has been solved analytically using Laplace transform method.

The effects of thermal Grashof number, solute Grashof number, nonlinear convection parameters, Casson fluid parameter, unsteady parameter, Prandtl number as well as Schmidt number on hydrodynamic, thermal and solute characteristics have been quantified. The numeric data for skin friction coefficient, Nusselt number and Sherwood number are presented. It is established the nonlinear convection aspect has a significant influence on heat and mass transport characteristics.

The effect of nonlinear convection in the dynamics of Casson fluid past an oscillating plate which is rotating non-axially is investigated for the first time.

The purpose of this paper is to introduce the Cattaneo-Christov heat flux model for an Oldroyd-B fluid.

Cattaneo-Christov heat flux model is utilized for the heat transfer analysis instead of Fourier’s law of heat conduction. Analytical solutions of nonlinear problems are computed.

The authors found that the temperature is decreased with an increase in relaxation time of heat flux but temperature gradient is enhanced.

No such analysis exists in the literature yet.

The aim of present work is to study the flow and heat transport structures of hybrid nanoparticles in a moving material. Two types of hybrid nanoparticles have been chosen namely Al₂O₃-Cu and Al₂O₃-Ag nanoparticles (90%) within 10% of pure water.

Leading governing equations are transformed through similarity technique and then computed for numerical illustration by applying RKF method.

The author observed that the skin friction value of Al₂O₃-Cu/water case is lesser in comparison to the values of Nusselt number for Al₂O₃-Ag/water nanoparticles.

There exist no such study which addressed such phenomenon.

The aim of this works is to characterize the role of Cattaneo?Christov heat flux in two-dimensional flows of second-grade and Walter’s liquid B fluid models.

In this study similarity transformations have been used to transform the system into ordinary ones. Numerical and analytical solutions are computed through homotopic algorithm and shooting technique.

The numerical values of temperature gradient are tabulated, and the temperature gradient reduces rapidly with enhancing values of the Darcy parameter, but this reduction is very slow for Forchheimer parameter.

No such analyses have been reported in the literature.

Presence of innumerable sensors, complex deduction of contexts from sensor data, and reusability of contextual information impose the requirement of middleware for context aware computing. Smart applications, hosted in myriad devices (e.g. PDA, mobile, PCs), acquire different contexts from the middleware and act intelligently based on the available contexts in a context‐aware computing environment. As the system grows larger, scalable delivery of contexts from the middleware to numerous context‐aware applications will be inevitable. However, pure unicast based or pure broadcast‐based dissemination cannot provide high scalability as well as low‐average latency. The purpose of this paper is to present a scalable context delivery mechanism for the middlewares to facilitate the development of larger context‐aware computing systems.

The proposed scheme is based on hybrid data dissemination technique where the most frequently requested data (e.g. HOT contexts) are delivered through multicast and the rest (e.g. COLD contexts) are delivered through unicast to reduce network traffic. The paper dynamically prioritizes and classifies the HOT and COLD context data depending on the number of requests and longest waiting time. Moreover, the division of bandwidth between the delivery of HOT and COLD contexts reduces average latency. Polling traffic is decreased by incorporating leasing mechanism. Extensive simulation is conducted to evaluate the proposed scheme.

The mechanism dynamically prioritizes and classifies the hot and cold context data depending on the request rate and longest waiting time. The solution addresses the push popularity problem that occurs in the passive as the passive clients access data without sending explicit requests. The leasing mechanism is incorporated to reduce the periodical requests (polling) for better performance.

The paper is of value in presenting a scalable context delivery mechanism for the middlewares to facilitate the development of larger context‐aware computing systems and also in presenting implementation details of a prototype that is developed using Jini framework and Java reliable multicast service (JRMS) library.

The study of novel exponential heat source (EHS) phenomena across a flowing fluid with the suspension of nanoparticles over a rotating plate in the presence of Hall current and chemical reaction has been an open question. Therefore, the purpose of this paper is to investigate the impact of EHS in the transport of nanofluid under the influence of strong magnetic dipole (Hall effect), chemical reaction and temperature-dependent heat source (THS) effects. The Khanafer-Vafai-Lightstone model is used for nanofluid and the thermophysical properties of nanofluid are calculated from mixture theory and phenomenological laws. The simulation of the flow is also carried out using the appropriate values of the empirical shape factor for five different particle shapes (i.e. sphere, hexahedron, tetrahedron, column and lamina).

Using Laplace transform technique, exact solutions are presented for the governing nonlinear equations. Graphical illustrations are pointed out to represent the impact of involved parameters in a comprehensive way. The numeric data of the density, thermal conductivity, dynamic viscosity, specific heat, Prandtl number and Nusselt number for 20 different nanofluids are presented.

It is established that the nanofluid enhances the heat transfer rate of the working fluids; the nanoparticles also cause an increase of viscous. The impact of EHS advances the heat transfer characteristics significantly than usual thermal-based heat source (THS).

The effectiveness of EHS phenomena in the dynamics of nanofluid over a rotating plate with Hall current, chemical reaction and THS effects is first time investigated.

The purpose of this paper is to study the Soret and Dufour effects in three-dimensional flow induced by an exponential stretching surface in a porous medium.

Series solutions are developed.

The authors observed that the temperature profile and thermal boundary layer thickness are enhanced when the authors increase the values of Dufour number. It is also examined that the concentration field and its associated boundary layer thickness are higher for the larger values of Soret number.

Such investigation is not available in the literature.

The purpose of this study is to scrutinize the effects of entropy generation and nonlinear mixed convection on the boundary layer flow of second grade fluid induced by stretching sheets. Heat transfer effects are accounted in view of viscous dissipation and nonlinear thermal radiation.

Optimal homotopic asymptotic method procedure is adopted to obtain the analytical solution of nonlinear ordinary differential equations.

It has been noticed that Hartmann and Brinkman number has reverse characteristics against entropy generation and Bejan number.

To the best of the authors’ knowledge, no such analysis has been reported to date.